The present disclosure relates to an optical scanning device, and particularly relates to an optical scanning device which is employed in a digital copier, a laser beam printer or the like and which carries out simultaneous writing with a plurality of laser beams. In order to reduce banding in prints produced by a raster output scanner (ROS) with multiple beams, it is often necessary to overwrite the exposed profile to average out nonuniformity caused by xerographic nonlinearities and beam power nonuniformity and misalignment. However, overwriting can waste ROS optomechanical bandwidth and driver bandwidth that could be used for applications such as increased image quality, electronic registration and microprinting. It is highly desirable to utilize this ROS bandwidth thereby enabling these applications.
Conventional overwriting presents a significant bandwidth challenge to the ROS while not fully utilizing that bandwidth, for example, the image path provides no more information bits to a ROS that is overwriting even though it is operating at twice the bandwidth. It is desirable to reap as many benefits as possible from a high bandwidth, overwriting ROS.